To find the numerical equivalent of the expression \( 4^9 \times 4^{-7} \), we can use the properties of exponents.
Specifically, the property \( a^m \times a^n = a^{m+n} \) allows us to combine the exponents:
\[ 4^9 \times 4^{-7} = 4^{9 + (-7)} = 4^{9 - 7} = 4^2 \]
Now, we can calculate \( 4^2 \):
\[ 4^2 = 16 \]
So, the numerical equivalent of \( 4^9 \times 4^{-7} \) is \( 16 \).
The correct answer from your options is:
16